Crystal and molecular structure of amarorine monohydrate, a new phenolic alkaloid from Amaroria soulameoides

Abstract

The molecular structure of amarorine (11-hydroxy-6H-indolo[3,2,1-de][1,5]naphthyridin-6-one)(I) and amaroridine (II), alkaloids isolated from Amaroria soulameoides A. Gray, were deduced by examination of their spectra; the structure of amarorine was confirmed by an X-ray crystallographic study. Crystals are monoclinic a= 17.44(3), b= 9.36(2), c= 7.12(2)Å, β= 92.7(1)°, Z= 4, space group P2₁/n. The structure was solved by direct methods and refined by full matrix least-squares calculations to R= 0.070 for 523 reflections.